Sep 13 2012
Topics Covered
IntroductionChemical CompositionPhysical PropertiesMechanical PropertiesThermal PropertiesFabrication and Heat Treatment Machinability Forming Welding Heat Treatment Cold Working Annealing Hardening
Introduction
Carbon steels are designated by AISI four-digit numbers. They contain carbon as the chief alloying element. Molybdenum, chromium, nickel, aluminium, and copper are present in small quantities. They also contain 1.2% of manganese and 0.4% of silicon.
The datasheet given bellows provides an overview of AISI 1145 carbon steel.
Chemical Composition
The following table shows the chemical composition of AISI 1145 carbon steel.
| Element |
Content (%) |
| Manganese, Mn |
0.69 |
| Carbon, C |
0.44 |
| Silicon, Si |
0.20 |
| Copper, Cu |
0.06 |
| Nickel, Ni |
0.04 |
| Sulfur, S |
0.038 |
| Phosphorous, P |
0.037 |
| Chromium, Cr |
0.03 |
| Arsenic, As |
0.024 |
| Aluminum, Al |
0.006 |
Physical Properties
The physical properties of AISI 1145 carbon steel are tabulated below.
| Properties |
Metric |
Imperial |
| Density |
7.7-8.03 g/cm3 |
0.278-0.290 lb/in3 |
Mechanical Properties
The mechanical properties of AISI 1145 carbon steel are outlined in the following table.
| Properties |
Metric |
Imperial |
| Elastic modulus |
190-210 GPa |
27557-30458 ksi |
| Poisson's ratio |
0.27-0.30 |
0.27-0.30 |
Thermal Properties
The thermal properties of AISI 1145 carbon steel are given in the following table.
| Properties |
Conditions |
| T (ºC) |
Treatment |
| Thermal expansion co-efficient (10-6/ºC) |
14.8 |
0-700 |
annealed |
Fabrication and Heat Treatment
Machinability
AISI 1145 carbon steel can be machined in the H16, 18 or 19 tempers.
Forming
AISI 1145 carbon steel can be formed using conventional techniques.
Welding
AISI 1145 carbon steel can be welded using commercial techniques such as TIG or MIG welding.
Heat Treatment
AISI 1145 carbon steel cannot be heat treated. However, it can hardened by cold working.
Cold Working
Cold working of AISI 1145 carbon steel can be easily carried out in softer tempers such H12, 14, 16 tempers, when compared to the harder tempers.
Annealing
AISI 1145 carbon steel can be annealed at 343°C (650°F) followed by air cooling.
Hardening
AISI 1145 carbon steel can be hardened by cold working.